Adjustable Volume Toddler Cup

ABSTRACT

Adjustable volume cups and methods for use are disclosed. One or more embodiments of the invention are directed to adjustable volume cups having a housing with at least one recess and a bottom slidably movable within the housing having at least one projection for cooperative interaction with the at least one recess.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part under 350 U.S.C. §120 of U.S. patent application Ser. No. 12/119,563, filed May 13, 2008, the contents of which are hereby incorporated by reference herein in their entirety.

FIELD OF THE INVENTION

The present invention is generally related to the field of toddler cups, and more specifically related to toddler cups with adjustable volumes.

BACKGROUND

There are a lot of toddler cups on the market designed to help a child transition from using a bottle to being able to drink from a regular cup. Even cups designed for the youngest toddler are typically designed to hold 4-6 oz. of liquid. A cup with only a couple ounces of liquid requires the child to mindfully manipulate the cup, by changing the angle of the cup, to continue to obtain liquid. Learning to tip the cup upward to continue finding liquid until the cup is empty requires much practice because the child needs to learn to tilt the cup upward and their heads backward at the same time.

A full cup of liquid mitigates this problem by decreasing the need for the child to angle the cup or their head. This results in countless wasted ounces of liquid because a young toddler may not drink more than an ounce at a time. Young toddlers beginning training with a cup may take only a few sips, but still the cup needs to be full to reinforce their efforts.

One way to reduce the waste associated with providing a full cup to a toddler is to use cups with smaller volumes. Using cups as small as the amount of liquid a toddler is likely to drink is impractical and expensive. Also, such a small cup (1 to 2 oz.) is likely to be difficult for a child to hold, thus creating a new problem with learning to use a toddler cup. For the benefit and ease of use of the toddler cup, children are best served by being able to hold a cup of normal size.

Another important issue parents face in raising our children is nutrition. Drinking too much juice or other high calorie liquids is a contributing factor to the crisis of obesity. Therefore, it is crucial for parents to be able to easily and accurately provide toddlers with well measured amounts of calorie-laden drinks.

As such, there remains a need in the art for cups which can help a child become accustomed to drinking from a regular cup.

SUMMARY

Embodiments of the invention may help toddlers cup train by allowing them to hold a full size cup while minimizing the headspace above the liquid. Additional embodiments allow a child to use a regular cup while being limited in the amount of calorie-laden drinks they consume. Embodiments of the invention may also allow parents to vary the amounts of liquids provided to their children, depending on age and the need at the time. This may result in monetary savings by reducing wasted liquids and the need to purchase multiple cups of various sizes.

FIG. 1 shows a full-sized toddler cup 100 with a spill-resistant lid 120 according to conventional art. It can be seen that when there is a small amount of liquid 140, relative to the volume of the cup 10 a large amount of air 160 is present. The air 160 may then be easily ingested by the drinker through the spill-resistant lid 120.

A cup 200 of one or more embodiments of the invention is shown in FIG. 2. By modifying the volume of the cup 200, in this case, by moving the bottom 280 of the cup 200 toward the lid 220, the amount of air 260 remaining in the cup 200 can be minimized. It can also be seen that the liquid 240 within the cup 200 covers more of the spill-resistant lid 220, thereby minimizing the amount of air ingested and reducing the likelihood of a child becoming ill.

Accordingly, one or more embodiments of the invention are directed toward variable volume cups. The cup of some embodiments comprises a housing having an inside surface and an outside surface. The housing is adapted to retain a substance. Retention may be effected in many ways. Some non-limiting examples include a separate bottom surface inside the cup (i.e., a cup that is shaped roughly like a soup can with one end removed), the inside surface can be frustum shaped, or the inside surface could taper to a point. The cup of some embodiments has at least one removable insert. The removable inserts may have an inside surface and an outside surface. The insert is adapted to fit within the housing and retain a substance.

Various embodiments of the invention have a removable cap adapted to fit on the cup. The removable cap of some embodiments comprises a spill-proof mechanism so a child can use the cup without risking spilling the contents. One skilled in the art will be familiar with spill-proof mechanisms which can be used with embodiments of the invention.

Further embodiments have a series of inserts stacked within the cup. Each insert can be stacked within either the cup housing or another insert within the housing. As an example of the stackable insert embodiments, a 12 oz. cup housing may have inserts which decrease the volume to 10, 8, 6 and 4 oz. Any single or combination of inserts can be employed by various aspects of the invention.

Some embodiments of the invention have handles attached to the housing. Other embodiments have handles attached to removable inserts. Handles attached to the inserts are accessible to a human hand when the at least one insert is within the housing. The handles attached to the inserts of multiple embodiments stack within the handles of subsequent inserts.

The housing of various embodiments comprises a gap between the inside surface and outside surface. Other embodiments have a gap between the outer surface and inner surface of the at least one removable insert. The gaps of these embodiments may be adapted to contain a substance. The substance of some embodiments can be frozen in a manner similar to an ice pack. This will serve to keep the contents of the cup cold.

Further embodiments of the invention are directed to a cup comprising an elongated housing having an inside surface and an outside surface. A bottom may be fitted within the housing in contact with the inside surface of the housing. A means for adjusting the location of the bottom within the inside of the housing is incorporated into certain embodiments. The inside surface and the bottom of these embodiments form a structure adapted for retaining a substance. The structure has a volume and a means for preventing a retained substance from passing between the inside surface and the bottom. The volume contained within the structure can be changed.

The means for adjusting the height of the bottom of the cup in various embodiments of the invention can be a screw-type mechanism, a slide mechanism, or combinations thereof. The screw-type mechanism can be, but is not required to be, attenuated by twisting a bottom portion of the housing, or some other radial motion. The slide-type mechanism can be, but is not required to be, a mechanism similar to a syringe plunger, but any mechanism requiring at least some axial force falls within the scope of embodiments of the invention.

Embodiments of the invention may incorporate handles which are accessible to a human hand to grip the cup.

Other embodiments have a gap between the inside surface and outside surface of the housing. The gap can hold a substance which may be adapted to retain either heat or cold, depending on the desired attributes for the liquid to be held. Some embodiments may have an insulating material on the outside of the housing. Other embodiments may have a housing having different materials on the inside surface and outside surface, allowing a person to hold the cup without their hand getting too cold or hot, depending on the contents of the cup.

Further embodiments of the invention are directed toward methods of using an adjustable volume cup. An insert having an inside surface and an outside surface may be placed within a housing. The housing also having an inside surface and an outside surface, so that the outside surface of the insert is in proximity to the inside surface of the housing. Both the housing and the insert are adapted to hold a substance.

Additional embodiments include attaching a cap having an opening for drinking to the housing. Further embodiments have a spill-proof mechanism incorporated into the cap.

Other embodiments further comprise the step of placing at least one second insert having an inside surface and an outside surface within the first insert so that the outside surface of the at least one second housing is in proximity to the inside surface of the first insert. Still further embodiments have a series of inserts stacked within each other, each subsequent insert decreasing the volume that the cup can hold.

Other embodiments are directed toward a method of using an adjustable volume cup, comprising filling a cup with a desired amount of liquid. The cup having an outside surface, an inside surface and a bottom in contact with the inside surface. The bottom is adapted to prevent liquid from passing between the inside surface of the cup and the bottom. The location of the bottom of the cup is adjusted, thereby determining the volume which the cup can hold.

Further embodiments include the step of attaching a cap having an opening for drinking to the housing. Still further embodiments incorporate a spill-resistant mechanism to the cap.

Various embodiments of the method include the step of freezing a substance located between the outside surface and the inside surface of the cup. The substance can also be heated to keep

One or more embodiments of the invention are directed to cups comprising a housing having axial length, an inside surface with at least one recess, an outside surface and an upper end. The cup includes a bottom slidably movable within the housing. The bottom having at least one projection shaped to cooperatively interact with the at least one recess. When inside the housing, the bottom is in contact with the inside surface of the housing to form a cup for retaining a substance.

Some embodiments have a removable cap. The cap of detailed embodiments comprises a threaded portion for rotatable connection with a threaded portion on the upper end of the outside surface of the housing.

In detailed embodiments, the at least one recess in the housing extends axially along the length of the housing. In specific embodiments, the at least one recess in the housing is dovetail shaped. In further specific embodiments, the bottom comprises at least one dovetail shaped projection sized to fit within the dovetail shaped recess of the housing.

In detailed embodiments, the at least one recess in the housing extends around the inside perimeter of the housing.

In specific embodiments, the at least one recess is arc shaped.

In one or more embodiments, the bottom comprises a plurality of expandable sections which upon expansion form a tight seal against the inside surface of the housing.

In detailed embodiments, the housing is cylindrical. In other detailed embodiments, the housing is rectangular (including square).

Further embodiments of the invention are directed to a cup comprising a cylindrical housing and a bottom. The cylindrical housing having an upper end and a lower end defining an axial length. The housing also having an outside surface and an inside surface with at least one recess. The bottom slidably movable within the housing along the axial length of the housing. The bottom including at least one projection having complementary shape to the at least one recess. When the bottom is in contact with the inside surface of the housing a cup is formed for retaining a fluid.

In detailed embodiments, the bottom further comprises a flexible ring around the perimeter of the bottom, the flexible ring compressible on contact with the inside surface of the housing to form a fluid tight seal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a convention drinking cup;

FIG. 2 shows a cup according to one or more embodiment;

FIG. 3 shows a cross-sectional view of a drinking cup according to another embodiment;

FIG. 4 shows a cross-sectional view of a drinking cup according to another embodiment;

FIG. 5 shows a cross-sectional view of a drinking cup according to another embodiment;

FIG. 6 shows a cross-sectional view of a drinking cup according to another embodiment;

FIG. 7 shows a cross-sectional view of a drinking cup according to another embodiment;

FIGS. 8A and 8B show a mechanism for moving a cup bottom according to another embodiment;

FIG. 9 shows a cross-sectional view of a drinking cup according to one or more embodiment of the invention;

FIG. 10 shows a partial isometric view of a drinking cup housing according to one or more embodiment of the invention;

FIG. 11 shows a partial isometric view of a drinking cup housing according to one or more embodiment of the invention;

FIG. 12 shows a bottom view of a drinking cup according to one or more embodiment of the invention;

FIG. 13 shows a bottom view of a drinking cup according to one or more embodiment of the invention;

FIG. 14 shows a partial isometric view of a drinking cup according to one or more embodiment of the invention;

FIG. 15 shows a partial isometric view of a drinking cup housing according to one or more embodiment of the invention;

FIG. 16 shows a partial isometric view of a drinking cup housing according to one or more embodiment of the invention; and

FIGS. 17A and 17B show a cup bottom in accordance with one or more embodiments of the invention.

DETAILED DESCRIPTION

Before describing several exemplary embodiments of the invention, it is to be understood that the invention is not limited to the details of construction or process steps set forth in the following description. The invention is capable of other embodiments and of being practiced or being carried out in various ways.

As used in this specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents unless the context clearly indicates otherwise. Thus, for example, reference to “an insert” includes a mixture of two or more inserts, and the like.

FIG. 3 shows a drinking cup according to one or more embodiments of the invention. The cup 300 shown, has a housing 310 with an exterior surface 320 and an interior surface 330 which define a volume 340. The housing 310 can be any shape, as desired by the specific cup design. Handles 350 are attached to the housing 310. A mechanism for attaching a top 360 is included, in this case it is a series of screw threads 370 a, 370 b. The top 360 may include a mouthpiece 380 adapted to be placed in the mouth for sipping. An insert 390 is shown which can be placed within the housing 310 to decrease the available volume for holding a liquid.

FIG. 4 shows a drinking cup 400 according to other embodiments. The handles 410 of this embodiment are a separate piece which may be attached to the cup 400. For example, the handles 410 may slide over a threaded section 420 at the top of the cup 400. A gap 430 between the housing exterior 440 and the housing interior 450 may be filled with a substance 460. This substance 460 may have a higher heat capacity than water, such that it will retain temperature longer than water. For example, the substance 460 may be frozen, thereby causing the contents of the cup to be kept cold. By using a substance with a higher heat capacity than water, the cup will substance 460 will retain its temperature longer. The insert 470 may also have a gap 480 which can be filled with a similar substance 490. The cup and/or the insert 470 can be filled with the substance.

FIG. 5 shows a drinking cup 500 according to further embodiments. The cup 50 of these embodiments has walls 510 and a bottom 520. The bottom 520 has an opening 530 which allows access to a sliding bottom 540. The sliding bottom 540 forms a seal with the inside of the wall 510 with a suitable sealing mechanism, in this case an o-ring 550 is used. The location of the sliding bottom 540 in the embodiment shown can be adjusted by inserting a rod 560 having a rod end 570 through the opening 530 and into a slot 580 in the sliding bottom 540. The rod end 570 can be fixed within the slot 580 allowing the sliding bottom 540 to be moved within the cup 500. Once the sliding bottom 540 has been moved to the desired location, the rod end 570 can be disengaged from the slot 580 and the rod 560 removed. The cup 500 of some embodiments has integral handles 590 with the cup 500 body.

FIG. 6 shows another cup 600 having a substance 610 within the walls 620 of the cup 600. The substance can also be located within the bottom 630 and the sliding bottom 640, as desired. The handles 650 of some embodiments can be a separate piece which may or may not be used with the cup 600.

The cup 700 of FIG. 7 uses a threaded rod 710 mechanism to adjust the location of the sliding bottom 720 within the cup walls 730. The sliding bottom 720 forms a seal with the cup walls 730 using a suitable sealing means. The sealing means shown in this drawing is an o-ring 740, but can be others. The location of the sliding bottom 720 can be adjusted by turning a handle 750 on the base of the cup 700. The threaded rod 710 in this embodiment occupies space within the inside of the cup 700. The walls 730 have markings 760 which can be read from the outside of the cup. The markings 760 can be used to indicate the volume that the cup 700 can hold. Thus, the sliding bottom 720 of the cup 700 can be positioned such that it aligns with one of the marks 760. Then the cup 700 will only be able to hold the amount of liquid shown on the mark 760. The threaded rod 710 of some embodiments holds a substance which can be frozen or heated.

FIG. 8A shows a view of a cup bottom 800 according to some embodiments. The cup bottom 800 has a series of tabs 810, 830, 850 which fold out on pivot pins 820, 840, 860. FIG. 8B shows a view of the same cup bottom 800 with the tabs 810, 830, 850 extended. By extending the tabs to the fully extended position, as shown in FIG. 8B, the user can pull or push on the tabs to cause the cup bottom 800 to move, thereby adjusting the volume of liquid that a cup can contain. The tabs shown are illustrative only, and the shape can be modified to suit any desired aesthetic or functional need.

An alternate embodiment of the invention is shown in cross-section in FIG. 9. An adjustable volume toddler cup 900 comprises a housing 910 and a bottom 940 slidably movable within the housing 910. The housing 910 has an axial length L, an inside surface 912 with at least one recess 915, an outside surface 914 and an upper end 918. The bottom 940 can slide within the housing 910 along the axial length L of the housing 910. The bottom 940 has at least one projection 945 shaped to cooperatively interact with the at least one recess 915 in the housing 910. The bottom 940 is in contact with the inside surface 912 of the housing 910 to form a cup 900 for retaining a substance.

The cup 900 shown in FIG. 9 includes a removable cap 950. The removable cap 950 may include a threaded portion 955. The upper end 918 of the cup 900 shown includes a threaded portion 925 on the outside surface 914 of the housing 910. The removable cap 950 of various embodiments incorporates a spill-proof mechanism. As used in this specification and the appended claims, “spill-proof mechanism” means that the mechanism decreases the likelihood of leakage if the cup is inverted. Suitable spill-proof mechanisms are known to those skilled in the art and generally incorporate a one-way valve (check valve) or an opening that causes surface tension to prevent spilling. The spill-proof mechanisms can be integrally formed with the cap or a separate piece that is inserted into the cap.

The cup 900 shown in FIG. 9 has at least two recesses 915 in the housing 910. However, various numbers of recesses 915 can be employed, and this should not be taken as limiting the scope of the invention. Additionally, the recesses 915 of FIG. 9 extend only partially along the axial length L of the housing 910. Again, this is merely illustrative and the recess 915 can extend completely along the axial length L of the housing 910.

The shape of the recess 915 can be selected based on the particular application. FIG. 10 shows a partial isometric view of a housing 1010 having a dovetail shaped recess 1015 extending along the axial length L of the housing 1010. FIG. 11 shows a partial isometric view of a housing 1110 having an arc- or circular-shaped recess 1115 extending along the axial length L of the housing 1110. In detailed embodiments, the recess 1015 is dovetail shaped.

FIG. 12 shows a bottom view of a cup 1200 including a housing 1210 having a plurality of recesses 1215 therein. A bottom 1240 is fitted within the housing 1210 having a plurality of projections 1245 sized and shaped to fit within the recesses 1215. The recesses 1215 of detailed embodiments are dovetail shaped. In specific embodiments, the recesses 1215 are symmetrically located (here, every 120°) within the housing 1210. In some detailed embodiments, the housing 1210 includes a plurality of dovetail shaped recesses 1215 and the bottom 1240 includes a plurality of dovetail shaped projections 1245 sized to fit within the dovetailed shaped recesses 1215 of the housing 1210. In other detailed embodiments, the recesses 1215 are located asymmetrically within the housing 1210.

The shape of the housing 1210 is shown in a cylindrical shape. This is merely illustrative and should not be taken as limiting the scope of the invention. In generally, the shape of the cup housing can be varied, both from cup-to-cup and within a single cup. The shape can be dynamic along the axial length to form a cup having a shape which fits comfortably within the hand. All shapes described herein should be taken a illustrative of a general shape only. It is contemplated that the sides of the housing can be sloped, undulating, or other shape. In specific embodiments, the housing is cylindrical. In other specific embodiments, the housing is rectangular. As used in this specification and the appended claims, the term “rectangular” includes square shapes. In further detailed embodiments, the housing is circular, rectangular (including square), octagonal, hexagonal, trigonal, pentagonal or oval in shape.

FIG. 13 shows a bottom view of a generally rectangular cup 1300 having a plurality of various shaped recesses 1315. A bottom 1340 is fitted within the housing 1310. The bottom 1340 includes a plurality of projections 1345 shaped to cooperatively interact with the recesses 1315 in the housing 1310. In detailed embodiments, the plurality of recesses, and cooperative projections, each have different shapes. This can make is easier to fit the bottom within the housing if a specific alignment is needed. A non-limiting example is a cup having three recesses where two are dovetail shaped and one is arc shaped.

FIG. 14 shows an alternate embodiment of a cup 1400 having a housing 1410 with a plurality of recesses 1415 extending around the inside perimeter of the housing 1410. Here, a plurality of recesses 1415 are spaced axially along the length L of the housing 1410, each recess 1415 running radially around the inside surface 1412 of the housing. The cup 1400 includes a bottom 1440 having a projection 1445 that fits within the radially extending recesses 1415.

The recesses 1415 may be located such that when the projection 1445 on the bottom 1440 is engaged with the recess 1415, the volume held by the cup is a predetermined amount. For example, the recesses may be spaced to create a volume of 2 oz, 4 oz, 6 oz, 8 oz or 10 oz.

FIG. 15 shows a partial isometric view of a detailed embodiment of the invention where the cup 1500 includes a housing 1510 with a plurality of rectangular (including square) shaped recesses 1515. FIG. 16 shows another partial isometric view of a detailed embodiment of a cup 1600 where the recesses 1615 in the housing 1610 arc shaped. These shapes should not be considered limiting of the scope of the invention and are merely illustrative.

FIG. 17 shows a detailed embodiment of a cup bottom 1740. This bottom 1740 includes a hub 1741, a plurality of expandable sections 1742 and a projection 1745 running around the outside perimeter of the bottom 1740. In a retracted state, shown in FIG. 17A, the expandable sections 1742 are retracted so that the projection 1745, which may be a simple rubber gasket, forms a bottom 1740 having a diameter d₁. Upon expansion, shown in FIG. 17B, the expandable sections 1742 are in the expanded state forcing the projection 1745 into an expanded form. This results in a bottom 1740 having a diameter d₂, which is greater than d₁. Thus, expansion of the plurality of expandable sections 1742 results in an increased diameter bottom 1740 which forms a tight seal against the inside surface of a cup housing. In detailed embodiments, the projection 1745 is made of a compressible material so that upon expansion of the expandable sections 1742, the projection 1745 is compressed, forming a tight seal with the inner surface of a cup housing.

In a detailed embodiment, the expandable sections 1742 may be moved between the retracted and expanded states by rotation of the hub 1741. In another detailed embodiment, the expandable sections 1742 may be moved between the retracted and expanded states by applying pressure to the hub 1741 in either the axial or radial direction (relative to the cup housing).

The hub 1741 can be any suitable shape, including, but not limited to, triangular, rectangular (including square), pentagonal, hexagonal, octagonal (as shown in FIG. 17), star shaped (like a Torx® screw), slit shaped (like a slotted screw), Pozidrive® shaped, Phillips shaped, etc. An insertion rod 560 (see FIG. 5) may be used to engage the hub 1741 in the bottom 1740 to expand the diameter. The hub shapes described are merely illustrative and should not be taken as limiting the scope of the invention.

The embodiments shown in FIG. 17 include eight expandable sections 1742 which expand from an octagonal hub 1741. This is merely illustrative and should not be taken as limiting the scope of the invention. The hub 1741 can have a different number of sides than the number of expandable sections 1742. Additionally, the number of expandable sections 1742 can be varied depending on the shape of the housing or preference.

A detailed embodiment of the invention is directed to cups comprising a cylindrical housing having an upper end and a lower end which define an axial length. The housing includes an outside surface and an inside surface with at least one recess. A slidably movable bottom is fitted with the housing. The bottom being movable along the axial length of the housing and including at least one projection having a complementary shape to the at least one recess. The bottom is in contact with the inside surface of the housing, forming a cup which can retain a fluid.

In a specific embodiment, the bottom further comprises a compressible or flexible ring around the perimeter of the bottom, the flexible ring being compressible on contact with the inside surface of the housing to form a fluid tight seal.

Accordingly, one or more embodiments of the invention are directed toward variable volume cups. The cup of some embodiments comprises a housing having an inside surface and an outside surface. The housing may be any shape, for example, an elongated cylinder, elongated octagon, or cubic. The housing is adapted to retain a substance being either a solid, liquid or gas. Retention may be effected in many ways. Some non-limiting examples include a separate bottom surface inside the cup (i.e., a cup that is shaped roughly like a soup can with one end removed), the inside surface can be frustum shaped, or the inside surface could taper to a point. The cup of some embodiments has at least one removable insert. The removable inserts have an inside surface and an outside surface. The inserts are adapted to fit within the housing and retain a substance.

Various embodiments of the invention have a removable cap adapted to fit on the cup. The removable cap of some embodiments comprises a spill-proof mechanism allowing a child to use the cup without risk of spilling the contents. One skilled in the art will be familiar with spill-proof mechanisms which can be used with embodiments of the invention.

Further embodiments have a series of inserts stacked within the cup. Each insert can be stacked within either the cup housing or within another insert within the housing. As an example of the stackable insert embodiments, a 12 oz. cup housing may have inserts which decrease the volume to 10, 8, 6 and 4 oz. Any single, or combination, of inserts can be employed by various aspects of the invention.

Some embodiments of the invention have handles attached to the housing. Other embodiments have handles attached to removable inserts. Handles attached to the inserts are accessible to a human hand when the at least one insert is within the housing. The handles attached to the inserts of multiple embodiments may stack within the handles of subsequent inserts.

The housing of various embodiments has a gap between the inside surface and outside surface. Other embodiments have a gap between the outer surface and inner surface of the at least one removable insert. The gaps of these embodiments may be adapted to contain a substance. The substance of some embodiments can be frozen in a manner similar to an ice pack. This will serve to keep the contents of the cup cold. In detailed embodiments the substance has a heat capacity that is higher than that of water.

Further embodiments of the invention are directed to a cup comprising an elongated housing having an inside surface and an outside surface. A bottom may be fitted within the housing in contact with the inside surface of the housing. A means for adjusting the location of the bottom within the inside of the housing is incorporated into certain embodiments. The inside surface and the bottom of these embodiments form a structure adapted for retaining a substance. The structure has a volume and a means for preventing a retained substance from passing between the inside surface and the bottom. The volume contained within the structure can be changed.

The means for adjusting the height of the bottom of the cup in various embodiments of the invention can be a screw-type mechanism, a slide mechanism, or combinations thereof. The screw-type mechanism can be, but is not required to be, attenuated by twisting a bottom portion of the housing, or some other radial motion. The screw mechanism can hold a substance adapted to be frozen or heated. The slide-type mechanism can be, but is not required to be, a mechanism similar to a syringe plunger, but any mechanism requiring at least some axial force falls within the scope of embodiments of the invention.

In a detailed embodiment, the cup bottom has a handle that can fold into the bottom. The handle of these embodiments can be extended, allowing the user to control the location of the bottom of the cup by pushing or pulling on the extended handle.

Other embodiments have a gap between the inside surface and outside surface of the housing. The gap can hold a substance which may be adapted to retain either heat or cold, depending on the desired attributes for the liquid to be held. Some embodiments may have an insulating material on the outside of the housing. Other embodiments may have a housing having different materials on the inside surface and outside surface, allowing a person to hold the cup without their hand getting too cold or hot, depending on the contents of the cup.

Further embodiments of the invention are directed toward methods of using an adjustable volume cup. An insert having an inside surface and an outside surface may be placed within a housing. The housing also having an inside surface and an outside surface, so that the outside surface of the insert is in proximity to the inside surface of the housing. Both the housing and the insert are adapted to hold a substance.

Additional embodiments include attaching a cap to the housing. The cap may have an opening for drinking. Detailed embodiments have a spill-proof mechanism incorporated into the cap.

Other embodiments comprise the step of placing at least one second insert having an inside surface and an outside surface within the first insert so that the outside surface of the at least one second housing is in proximity to the inside surface of the first insert. Still further embodiments have a series of inserts stacked within each other, each subsequent insert decreasing the volume that the cup can hold.

Other embodiments are directed toward a method of using an adjustable volume cup, comprising filling a cup with a desired amount of liquid. The cup having an outside surface, an inside surface and a bottom in contact with the inside surface. The bottom is adapted to prevent liquid from passing between the inside surface of the cup and the bottom. The location of the bottom of the cup is adjusted, thereby determining the volume which the cup can hold. The location of the cup bottom can be adjusted before or after addition of the substance to the cup.

Various embodiments of the method include the step of freezing a substance located between the outside surface and the inside surface of the cup. The substance can also be heated to keep the substance warm.

Accordingly, while the present invention has been disclosed in connection with various embodiments thereof, it should be understood that other embodiments might fall within the spirit and scope of the invention, as defined by the following claims.

Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents. 

1. A cup comprising: a housing having axial length, an inside surface with at least one recess, an outside surface and an upper end; and a bottom slidably movable within the housing and having at least one projection shaped to cooperatively interact with the at least one recess, when inside the housing the bottom in contact with the inside surface of the housing to form a cup for retaining a substance.
 2. The cup of claim 1, further comprising a removable cap.
 3. The cup of claim 2, wherein the removable cap comprises a threaded portion for rotatable connection with a threaded portion on the upper end of the outside surface of the housing.
 4. The cup of claim 1, wherein the at least one recess in the housing extends axially along the length of the housing.
 5. The cup of claim 4, wherein the at least one recess in the housing is dovetail shaped.
 6. The cup of claim 5, wherein the bottom comprises at least one dovetail shaped projection sized to fit within the dovetail shaped recess of the housing.
 7. The cup of claim 1, wherein the at least one recess in the housing extends around the inside perimeter of the housing.
 8. The cup of claim 7, wherein the at least one recess is arc shaped.
 9. The cup of claim 1, wherein the bottom comprises a plurality of expandable sections which upon expansion form a tight seal against the inside surface of the housing.
 10. The cup of claim 1, further comprising handles attached to the housing.
 11. The cup of claim 2, wherein the removable cap comprises a spill-proof mechanism.
 12. The cup of claim 1, wherein the housing has a gap between the inside surface and outside surface, the gap for containing a substance.
 13. The cup of claim 12, further comprising a substance contained within the gap, the substance being able to be frozen.
 14. The cup of claim 1, wherein the cup further comprises markings viewable from the outside surface, each marking denoting the volume containable within the cup when the bottom is positioned at the mark.
 15. The cup of claim 1, wherein the housing is cylindrical.
 16. The cup of claim 1, wherein the housing is rectangular.
 17. A cup comprising: a cylindrical housing having an upper end and a lower end defining an axial length, an outside surface and an inside surface with at least one recess; and a bottom slidably movable within the housing along the axial length of the housing, the bottom including at least one projection having complementary shape to the at least one recess, the bottom in contact with the inside surface of the housing forming a cup for retaining a fluid.
 18. The cup of claim 17, wherein the bottom further comprises a flexible ring around the perimeter of the bottom, the flexible ring compressible on contact with the inside surface of the housing to form a fluid tight seal. 